目的

探讨凋亡抑制蛋白抑制剂LCL161 对人三阴性乳腺癌细胞株MDA-MB-231 增殖的影响。

方法

(1)体外实验:将乳腺癌MDA-MB-231 细胞分为6 组, 对照组不接受任何药物处理, 其余5 组分别给予1、10、100 nmol/L 和1、10 μmol/L LCL161 溶液处理。 用MTT 法检测LCL161 对乳腺癌细胞株MDA-MB-231 增殖能力的影响,分别于24、48、72 h 在酶标仪上检测490 nm 波长下吸光度值,每组重复5 次;(2)体内实验:建立人乳腺癌裸鼠种植瘤模型,用随机数字表法分为3 组:对照组、LCL161 组、多柔比星组,每组10 只。 对照组每只予以灌胃法注射醋酸钠溶液0.2 ml 及腹腔注射0.9%NaCl 溶液0.2 ml,LCL161 组每只予以灌胃法注射LCL161 30 mg/kg 及腹腔注射0.9%NaCl 溶液0.2 ml,多柔比星组每只予以灌胃法注射醋酸钠溶液0.2 ml 及腹腔注射多柔比星20 mg/kg。 灌胃法注射每周2 次,腹腔注射每2 日1 次。 2 周后停止给药。 分别于停药后第5、8、11、14、17、20 天检测各组裸鼠种植瘤的体积。之后处死裸鼠,皮下剥离肿瘤,称取各组肿瘤质量。 各组吸光度值、种植瘤体积及质量用±s 表示,样本间均数比较采用重复测量因素的方差分析和单因素方差分析。

结果

(1) 体外实验显示不同药物浓度组吸光值差异有统计学意义(F=928.69,P＜.001)。 3 个时间点吸光度值之间差异有统计学意义(F=34.77,P＜.001)。 药物浓度与时间之间有交互作用(F=98.50,P＜.001)。 (2)体内实验各组小鼠种植瘤体积,各组间比较差异有统计学意义(F=257.38,P＜.001)。 不同时间点小鼠种植瘤体积之间比较差异有统计学意义(F=1907.00,P＜.001)。 分组与时间之间存在交互作用(F=103.63,P＜.001)。对照组、多柔比星组及LCL161 组小鼠种植瘤的平均体质量分别为(1.83±0.23)、(0.85±0.06)、(0.70±0.10) g,差异有统计学意义(F=174.82,P＜.001)。

结论

LCL161 能抑制MDA-MB-231 细胞的增殖,对活体裸鼠体内MDA-MB-231 种植瘤的生长具有抑制作用,有望成为治疗三阴性乳腺癌的新靶点药物。

Objective

To investigate the effect of LCL161 on the proliferation of human triple-negative breast cancer MDA-MB-231 cells.

Methods

(1) In in vitro experiment, the breast cancer MDA-MB-231 cells were divided into six groups: control group did not receive any drug treatment, and the other 5 groups were given 1,10,100 nmol/L and 1,10 μmol/L LCL161 solution respectively. Using MTT assay, the optical density at 490 nm wavelength on a microplate reader was detected at 24,48,72 h after treatment to reflect the proliferation of breast cancer MDA-MB-231 cells. The measurement was repeated five times to get mean values.(2) In in vivo experiment, the mouse model with the seeding of human breast cancer cells was established.The mice were randomly divided into three groups: control group, LCL161 group and doxorubicin group,10 mice in each group. The control group was given gavage injection of 0.2 ml sodium acetate solution per mouse and intraperitoneal injection of 0.2 ml saline per mouse, LCL161 group was given gavage injection of LCL161 30 mg/kg and intraperitoneal injection of 0.2 ml saline per mouse, and doxorubicin group was given gavage injection of 0.2 ml sodium acetate solution per mouse and intraperitoneal injection of doxorubicin 20 mg/kg. The gavage injection was given twice per week, intraperitoneal injection once every 2 days. The drug administration lasted for 2 weeks. The volume of implanted tumor in mice of each group was measured on days 5, 8, 11, 14, 17 and 20 after drug withdrawal. Then the mice were sacrificed, the tumor was subcutaneously removed and the weight of tumor was measured. The optical density, volume and weight of implanted tumor in each group were expressed as ±s, and compared using repeated measurement or one-way analysis of variance.

Results

(1) In vitro experiment showed that the optical density was significantly different among groups with different LCL161 concentrations (F=928.69,P＜0.001) and among three time points (F=34.77,P＜0.001); there was an interaction between drug concentration and time (F= 98.50,P＜0.001). (2) In vivo experiment showed that implanted tumor volume of mice was significantly different between groups (F=257.38,P＜0.001) and among different time point (F=1907.00,P＜0.001); there was an interaction between grouping and time (F=103.63,P＜0.001). The weight of implanted tumor was (1.83 ±0.23) g in control group, (0.85 ± 0.06) g in doxorubicin group and (0.70 ± 0.10) g in LCL161 group,respectively, and the difference was statistically significant (F=174.82,P＜0.001).

Conclusion

LCL161 can inhibit the proliferation of MDA-MB-231 cells and thus repress the growth of tumor induced by MDA-MB-231 cells in mice, with potentials as a new target drug for the treatment of triple-negative breast cancer.